Trying to fix my NES

[FinalSmash]

Okay, so I brought home my mom's old NES from my grandparent's on Friday, but it doesn't work; you know, the flashing power LED and the blinking blue or white screen? Yeah. I cleaned the 72 pin connecter by boiling it in water(yeah I know weird right?), but it still doesn't work. I'm cleaning the motherboard right now, so does anyone have any tips/tricks that will help? They'd be greatly appreciated.